Select all faces parallel to ground
I would use c for circle select and pick the top parts of the globes then either grow selection or use select similar.

Select similar which is Shift + g can be used to find faces with similar angles/direction which should be your best bet. Then just grow your selection using 
Ctrl + +
More ways to select can be found here https://docs.blender.org/manual/en/latest/modeling/curves/selecting.html